Air bag restraint systems for vehicles are well known in the art. It is also known to prevent deployment of an air bag during a vehicle collision when the air bag is associated with a seat location that is unoccupied. Deployment of an air bag associated with an unoccupied seat location (typically the passenger seat location) during a vehicle collision adds unnecessary expense to the repair of the vehicle.
To prevent such unnecessary deployment of an air bag at an unoccupied seat location, sensors are provided to detect the presence of an occupant on a vehicle seat. These sensors include pressure sensing switches located in the seat cushion and/or infrared or ultrasonic sensors located in the vehicle dashboard or instrument panel. If no occupant is detected as being present on the seat, deployment of the associated air bag during a vehicle collision is prevented through an appropriate control arrangement.
It is also desirable to prevent deployment of an air bag when a child restraint seat is secured in a rearward facing direction on the vehicle seat associated with the air bag.